:root {
    --primary-color: #1a2b3d;
    --secondary-color: #e67e22;
    --accent-color: #3498db;
    --background-color: #f7f9fc;
    --card-background: #ffffff;
    --text-color: #2c3e50;
    --muted-text-color: #7f8c8d;
    --border-color: #e1e8ed;
    --success-color: #27ae60;
    --shadow: 0 4px 15px rgba(0, 0, 0, 0.08);
    --font-family: 'Poppins', sans-serif;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: var(--font-family);
    background-color: var(--background-color);
    color: var(--text-color);
    line-height: 1.6;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

header {
    background-color: var(--primary-color);
    color: white;
    padding: 1.5rem;
    text-align: center;
    box-shadow: var(--shadow);
}

header h1 {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 0.25rem;
}

header p {
    font-weight: 400;
    opacity: 0.9;
}

main {
    flex: 1;
    padding: 1.5rem;
    padding-bottom: 100px; /* Space for nav bar */
}

.screen {
    display: none;
}

.screen.active {
    display: block;
}

h2 {
    font-weight: 600;
    margin-bottom: 1rem;
    color: var(--primary-color);
}

/* Buttons */
.primary-btn {
    background-color: var(--secondary-color);
    color: white;
    border: none;
    padding: 1rem 2rem;
    border-radius: 50px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: background-color 0.3s, transform 0.2s;
    width: 100%;
    margin-top: 1.5rem;
    box-shadow: 0 4px 10px rgba(230, 126, 34, 0.3);
}

.primary-btn:hover {
    background-color: #d35400;
    transform: translateY(-2px);
}

.primary-btn:active {
    transform: translateY(0);
}

/* Card Component */
.card {
    background-color: var(--card-background);
    border-radius: 12px;
    padding: 1.5rem;
    box-shadow: var(--shadow);
    margin-bottom: 1.5rem;
}

.card h3 {
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: var(--primary-color);
}

/* Filter Buttons */
.filter-buttons {
    display: flex;
    justify-content: center;
    gap: 0.5rem;
    margin-bottom: 1.5rem;
}

.filter-btn {
    background-color: var(--card-background);
    border: 1px solid var(--border-color);
    padding: 0.5rem 1.25rem;
    border-radius: 50px;
    cursor: pointer;
    font-size: 0.9rem;
    font-weight: 500;
    transition: all 0.2s;
}

.filter-btn.active {
    background-color: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

/* Grouped List */
.produce-list {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.produce-group {
    background-color: var(--card-background);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: var(--shadow);
}

.group-header {
    background-color: var(--card-background);
    padding: 1rem 1.5rem;
    font-weight: 600;
    font-size: 1.1rem;
    color: var(--primary-color);
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.group-header .arrow {
    transition: transform 0.2s ease-in-out;
}

.produce-group.collapsed .arrow {
    transform: rotate(-90deg);
}

.produce-group .group-items {
    max-height: 1000px;
    transition: max-height 0.3s ease-in-out, padding 0.3s ease-in-out;
    padding: 0.5rem 1.5rem 1rem;
}

.produce-group.collapsed .group-items {
    max-height: 0;
    padding: 0 1.5rem;
    overflow: hidden;
}

.produce-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem 0;
    border-bottom: 1px solid var(--border-color);
}

.produce-item:last-child {
    border-bottom: none;
}

.produce-item .info h3 {
    font-size: 1rem;
    font-weight: 500;
    margin-bottom: 0;
}

.produce-item .actions {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.produce-item input[type="checkbox"] {
    width: 1.25rem;
    height: 1.25rem;
    cursor: pointer;
    accent-color: var(--secondary-color);
}

.produce-item button {
    background: none;
    border: none;
    font-size: 1.25rem;
    cursor: pointer;
    color: var(--accent-color);
    padding: 0.25rem;
    transition: color 0.2s;
}

.produce-item button:hover {
    color: var(--secondary-color);
}

/* Tabs */
.tabs {
    display: flex;
    margin-bottom: 1.5rem;
    border-bottom: 2px solid var(--border-color);
}

.tab-button, .plan-tab-button {
    background: none;
    border: none;
    padding: 0.75rem 1rem;
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    color: var(--muted-text-color);
    border-bottom: 3px solid transparent;
    flex-grow: 1;
    transition: color 0.2s, border-color 0.2s;
}

.tab-button.active, .plan-tab-button.active {
    color: var(--secondary-color);
    border-bottom-color: var(--secondary-color);
}

.tab-content {
    display: none;
}
.tab-content.active {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

/* Meal Plan Screen */
.plan-content {
    background-color: var(--card-background);
    border-radius: 12px;
    padding: 1.5rem;
    box-shadow: var(--shadow);
}

.meal-day {
    display: none;
}

.meal-day.active {
    display: block;
}

.meal-item {
    border-bottom: 1px solid var(--border-color);
    padding: 1rem 0;
    cursor: pointer;
    transition: background-color 0.2s;
}

.meal-item:last-child {
    border-bottom: none;
}

.meal-item:hover {
    background-color: var(--background-color);
    margin: 0 -1.5rem;
    padding-left: 1.5rem;
    padding-right: 1.5rem;
}

.meal-item h4 {
    font-weight: 600;
    color: var(--primary-color);
}

.placeholder-text {
    text-align: center;
    color: var(--muted-text-color);
    padding: 2rem;
}

/* Modals */
.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    overflow: auto;
    background-color: rgba(0,0,0,0.5);
    animation: fadeIn 0.3s;
}

.modal-content {
    background-color: var(--card-background);
    margin: 10% auto;
    padding: 2rem;
    border-radius: 12px;
    width: 90%;
    max-width: 500px;
    box-shadow: 0 5px 25px rgba(0,0,0,0.2);
    animation: slideIn 0.3s;
    position: relative;
}

.close-btn {
    color: var(--muted-text-color);
    position: absolute;
    top: 1rem;
    right: 1.5rem;
    font-size: 2rem;
    font-weight: 300;
    cursor: pointer;
}

.modal h3 {
    margin-bottom: 1rem;
}

.modal-subtext {
    font-size: 0.9rem;
    color: var(--muted-text-color);
    margin-top: 1rem;
    text-align: center;
}

.output-box {
    background-color: var(--background-color);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 1rem;
    margin: 1rem 0;
}

#modal-output-text {
    white-space: pre-wrap;
    word-wrap: break-word;
    font-family: 'Courier New', Courier, monospace;
    font-size: 0.9rem;
    max-height: 150px;
    overflow-y: auto;
}

#modal-copy-btn {
    width: 100%;
}

/* Navigation Bar */
nav {
    position: fixed;
    bottom: 0;
    left: 0;
    width: 100%;
    background-color: var(--card-background);
    border-top: 1px solid var(--border-color);
    display: flex;
    justify-content: space-around;
    padding: 0.5rem 0;
    box-shadow: 0 -2px 10px rgba(0,0,0,0.05);
}

.nav-button {
    background: none;
    border: none;
    color: var(--muted-text-color);
    cursor: pointer;
    padding: 0.5rem;
    transition: color 0.2s;
    font-size: 0.75rem;
    font-weight: 500;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.25rem;
}

.nav-button .nav-icon {
    font-size: 1.25rem;
}

.nav-button.active {
    color: var(--secondary-color);
}

footer {
    text-align: center;
    padding: 0.5rem;
    font-size: 0.8rem;
    color: var(--muted-text-color);
}

/* Animations */
@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes slideIn {
    from { transform: translateY(-50px); opacity: 0; }
    to { transform: translateY(0); opacity: 1; }
}